[unreadable] A new method for removal of airborne particles from air by bubbling through porous medium immersed into liquid has been developed and shown to be efficient for cleaning environments with ultra-fine particles. Some studies have demonstrated that the new technique can be suitable for collecting viable airborne microorganisms even if they are sensitive to stress. The principal objective of the present study at the initial stage of investigation (R21) is to evaluate the new bubbling technique for collection of viable airborne microorganisms, including viruses, bacteria and fungi into appropriate liquids for subsequent physical and microbiological analysis. The main expected outcomes of the entire study (R21/R33) will be a new methodology and a fully functional prototype of equipment for representative personal sampling of viable airborne microorganisms. Accurate and reliable information about concentration of pathogenic viable airborne microorganisms in ambient air is one of the most important issues in biomedical research for evaluation of health effects. Other potential users of the device are security and antiterrorist units that deal with the detection and quantification of airborne biological agents. The main aims will be achieved through extensive laboratory research together with field evaluation of the new equipment. The laboratory research will be conducted by using most advanced equipment available for the bioaerosol evaluation including monitoring of physical collection efficiency of the sampler by Scanning Mobility Particle Sizer (TSI, USA) and Laser Particle Counter. Microorganism recovery rates will be identified by using culturing technique for bacteria and fungi and by virus titration technique for viruses. Also, nature and total amount of particular microorganisms of interest collected during field studies will be identified by standard PCR technique (DNA microorganisms) and RT - PCR (RNA microorganisms). Field evaluation will be performed in different environments including low concentrated areas (offices and residential buildings) and highly concentrated areas (agriculture and waste management facilities). The new personal sampler will become a first available technique suitable for monitoring viable airborne viruses in an ambient air and first personal sampling technique capable to provide eight hours non-stop operation. [unreadable] [unreadable]